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Hourly Forecast
Daylight Hours
07:23
Sunrise
19:33
Sunset
Moon
Waxing Crescent
11:43
Moonrise
21:36
Moonset
Daily Forecast
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Air Quality Data Available
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UV Index
Humidity
Weather in San Antonio today, September 15, 2026
Conditions in San Antonio on September 15, 2026 favour clear skies, so the day opens with a fine, sunny outlook. Any interruptions to the blue should be brief rather than lasting. The opening hours look fair, as cloud stays near 35% around 09:00. Morning errands should face fewer weather interruptions.
The day peaks near 38°C and cools toward 26°C. The air stays humid, with relative humidity between 26% and 92% and the peak around 07:00. Winds stay light, near 5.8 km/h by 20:00, so the day feels still more than breezy.
Expect a more open afternoon, with limited cloud around 58% by 15:00. Residual damp risk should be lower than earlier. Horizontal visibility sits around 15.6 km, briefly nearer 13.0 km. The sun rises at 07:23 and sets at 19:33, for a total of 12 hours 10 minutes of sunlight today.
Taken together, settled sunshine in San Antonio on September 15, 2026 makes outdoor timing easier, with highs near 38°C.
Frequently asked questions about weather in San Antonio
How warm does it get in San Antonio?
The warmest month in San Antonio is August, with average high temperatures of 36°C. The average temperature during this period is around 30°C.
How cold does it get in San Antonio?
The coldest month in San Antonio is January, with average low temperatures of 6°C. The average temperature during this period is around 11°C.
What is the wettest time of year in San Antonio?
The wettest month in San Antonio is May, with an average of 111mm of precipitation.
What is the driest time of year in San Antonio?
The driest month in San Antonio is February, with an average of 45mm of precipitation.
